A judge says a Virginia pastor must testify before a grand jury investigating the kidnapping of a now-10-year-old girl by her mother, who refused to share custody with the Vermont woman who was once her civil union partner.

Court documents say 46-year-old Kenneth Miller of Stuarts Draft, Va., had asked a judge to quash a subpoena, but he refused. The judge says prosecutors have guaranteed Miller immunity for anything he says before the grand jury.

Miller was convicted in August of helping Lisa Miller flee the country with daughter Isabella in September 2009. The Millers are not related.